Creation of Bio-photocatalyst Using Microorganism with Artificial Light-driven Coenzyme Regeneration System

2019 Fiscal Year Final Research Report

• Project/Area Number: 18K14376
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 38020:Applied microbiology-related
• Research Institution: Nara Women's University
• Principal Investigator: Honda Yuki 奈良女子大学, 自然科学系, 助教 (90583849)
• Project Period (FY): 2018-04-01 – 2020-03-31
• Keywords: 光触媒 / 生体触媒 / 水素生産 / 補酵素再生

Outline of Final Research Achievements

Biocatalysts, including enzymes or microorganisms, are capable of catalyzing highly selective and efficient reactions under environmentally friendly condition. This feature of biocatalysis would contribute to developing an energy-saving process in industry. In an industrial application of biocatalysis, supplying energy to proceed a certain reaction has been a problem in the enzymatic reaction which requires a coenzyme, such as NADH. This study addressed this problem by developing a light-driven biocatalysis system which consists of the combination of photosensitizer and enzyme. In such system, photosensitizer serves energy to enzyme from light energy, instead of costly coenzyme supplementation. This study achieved a large-scale synthesis of porphyrin dye by genetically engineered bacteria, the photoreduction of an artificial coenzyme (MV) by the dye, and one of the light-driven biocatalysis by coupling the photoreduction of MV and the hydrogen-forming enzyme.

Free Research Field

応用微生物学

Academic Significance and Societal Importance of the Research Achievements

酵素反応の利用において、反応の進行に必要な補酵素の再生は重要な課題であった。グルコース脱水素酵素との共役反応などは古くから用いられる補酵素再生系であり、また種々の方法が考案されている。本研究では、安価に入手できる光によって、かつ生体分子によって酵素へのエネルギー供給を実現する新規な反応系を構築し、新たな方法論による補酵素再生の実現を目指した。補酵素再生という課題に対して、従来とは異なる方法論で解決を目指す点で学術的な意義があり、かつ、その効果は生体触媒の工業的利用による省エネルギープロセスの実現に寄与することが期待されるころから、社会的な意義のある研究提案であった。